a 
bone dust been in a normal condition, its effect would have 
certainly not much inferior to that of the superphosphate on the 
first crops. On the other hand, there is no great difference in the 
assimilability of the phosphoric acid of the crude bone dust and 
raw crushed bones. These two manures had a good effect on the 
first two crops, but after having undergone decomposition in the 
in the soil for one year, their solubility increased so enormously 
that the third crop consumed from them more than even the 
superphosphate yielded to the first crop. This observation is of 
great practical importance. It goes to show that in countries with 
a warm climate and with copious rain, as in Japan, bone manures' 
are most valuable even in quite a raw state, and that by early 
application or by a preparatory fermentation in the compost bed 
their manurial value may be easily and cheaply raised to that of 
the superphosphate. During our experiments on the college farm 
we have had frequent opportunity of proving that bone dust has a 
specially good effect on cereals sown in autumn, not only in 
reference to its phosphatic ingredients but also to its content of 
nitrogen. The presence of fat does not deteriorate its value, but 
seems rather to secure a better after-effect, as in our experiments 
the raw crushed bones with 14.07 % fat yielded more phosphoric 
acid to the 3rd and 4th crops than the crude bone dust with only 
1.33 fat. 
4. The Thomas phosphate displayed with regard to the first crop 
as well as to the 3 subsequent ones approximately half the effect 
of the superphosphate. The excellent after-effect attributed to this 
fertilizer by P. Wagner has not been, up to the present, percep¬ 
tible in our experiments, in spite of the richness of our soil in 
humus, and the copious rainfall. 
5. Bone ash is, as we had anticipated, a very insoluble manure 
acting but slowly on the first two crops, but of increased efficacy 
in course of time. It should always be converted into superphos¬ 
phate before its application. 
